1. Field of the Invention
The present invention concerns an abrasive-containing liquid cleaning composition for removing organic deposits from hard to reach surfaces and a method of use thereof. More specifically, the invention concerns to an easy to rinse cleaning composition that cleans and disinfects at the same time.
2. Description of the Related Art
The use of cleaning compositions to remove organic deposits is well known in the prior art. Effective removal of organic deposits is a considerable problem, which in the past has required the use of highly corrosive, unsafe cleaners, typically based on highly alkaline caustics such as sodium or potassium hydroxide, sometimes accompanied by laborious scrubbing and/or scraping.
Further, caustic cleaners require substantially elevated temperatures to work effectively and are extremely difficult to remove by rinsing. Many caustic cleaners, such as those incorporating sodium hydroxide, damage the skin of the user and produce hazardous fumes. Such caustic cleaners can also scar, damage and even destroy many types of surfaces. The use of these products also raises serious hazards to the skin and eyes of the user.
Another problem presented by the use of these products is that the chemicals fill the air of the building in which they were used causing eye, nasal, and lung irritation. After the cleaning solution dries, then the residual chemical and mineral precipitates (solids) flake off and become airborne, and further irritate eyes, nose, lungs, and skin. The aforesaid residual chemicals and mineral precipitates may trigger allergies, asthma attacks, and other sinus and respiratory problems.
To avoid the problems associated with caustic cleaners, non-caustic cleaners, which are typically not as effective as caustic cleaners, are employed in many applications. Because of the reduced effectiveness of the non-caustic cleaners, additional time and labor is required to remove organic deposits. Non-caustic cleaners are sometimes initially used to remove a portion of the organic deposits with the remainder being removed by caustic cleaners. In this manner, the use of caustic cleaners is reduced as much as possible.
Another problem encountered with the prior art is that while organic deposits are generally easy to remove from relatively flat surfaces, it is very difficult to remove the organic deposits from cracks, crevices, corners, passages, and other hard-to-reach places.
In view of the difficulty of the cleaning compositions discussed above to access or adequately clean hard to reach surfaces of a substrate, there has been a recent trend to employ liquid cleanser that breaks down and removes residue or scale in the hard to reach surfaces.
A problem presented with these liquid compositions is that they merely provide a pre-soaking treatment and require brushing to remove deposits. Thus, areas not reached by a brush are not cleaned. This problem becomes acute in the case of convoluted or sharp angled corners, passages, or other pieces.
The prior art compositions require soaking for at least about one-half hour and constant scrubbing for satisfactory removal of the deposit, which is particularly difficult to achieve in hard-to-reach places.
For example, U.S. Pat. No. 5,858,106 entitled xe2x80x9cCleaning Method for Peeling and Removing Photoresistxe2x80x9d to Ohmi et al., teaches a cleaning liquid composition comprised of pure water, isopropyl alcohol, and hydrofluoric acid, ammonium fluoride, or potassium fluoride. The cleaner is used to peel organic films such as photoresists off of a semiconductor. The cleaning liquid is used together with ultrasound. A problem presented with this reference is that the cleaner is potentially toxic, and would be difficult for the average consumer to use.
Another cleaner is disclosed in U.S. Pat. No. 5,041,235 xe2x80x9cLiquid Hard Surface Cleaner for Porous Surfacesxe2x80x9d to Kilbarger. This patent discloses a liquid hard surface cleaner for porous surfaces. The composition contains a surfactant, a synthetic hydrocarbon oil, and an aliphatic alcohol. This composition, is used for hard to reach surfaces, but presents the problem that it leaves a residue on the internal surfaces of the substrate.
Finally, U.S. Pat. No. 4,496,667 entitled xe2x80x9cMethod for Cleaning Organically Fouled Anion Exchange Resinsxe2x80x9d to Reichgott et al. discloses cleaning organically fouled anion exchange resins by first pre-soaking the resins in a brine-caustic solution for one hour, rinsing with distilled water, soaking in a brine-caustic 30% isopropanol solution for one hour, rinsing, and repeating the second soaking step. The use of a one to four carbon monohydric alcohol in the second soaking step was found to provide a 100% improvement in resin removal. This process is both time-consuming (taking at least three hours) and complex.
The present inventor became familiar with the various commercially available liquid cleansers, and felt that the long period of soaking was a significant inconvenience. Determined to find a better liquid cleanser, the inventor began experimenting with various household detergent products, such as glass cleaners, tile cleaners, carpet cleaners, etc. He quickly realized that most of these products could be eliminated from consideration due to the unpleasant and possibly toxic residues left behind after cleaning.
Accordingly, the present inventor felt a need for a non-hazardous cleaning composition for removing organic deposits that is safe to use and will not damage the surfaces to be cleaned. Particularly, he felt that there is a need to provide a cleaning composition that will not damage the skin of the user.
Also, there is a need for a non-toxic cleaning composition that does not leave a visible residue.
Further, there is a need for a non-toxic product, which can be used for users having allergy problems.
Further, it can be appreciated that there exists a need for a cleansing composition for cleaning and disinfecting hard to reach surface of a substrate that is capable of removing organic deposit on the hard to reach surface quickly and in a single cleaning cycle.
Finally, there remains a need in the art for cleaning compositions which include an abrasive that exhibits improved performance, is less expensive, easy to handle, easy to disperse in the substrate and would not leave residue in the hard to reach surface or the substrate.
It is therefore an object of the present invention to provide a cleaning composition that represents a vast improvement over the above-discussed cleaning compositions.
It is yet another object of the invention to provide cleaning compositions, which effectively remove organic deposits on hard to reach surfaces without having a detrimental effect on the substrate.
It is yet another object of the present invention to provide a cleaning composition which achieves cleaning and disinfecting in a much shorter time, without scrubbing, as compared to conventional cleaning compositions.
It is yet another object of the present invention to provide a cleaning composition that does not leave a visible residue.
It is yet another object of the present invention to provide a cleaning composition that can be used by users having allergy problems or customer that prefer natural product.
The present inventor surprisingly found that a stable, easy to rinse cleaning composition that overcomes or minimizes the drawbacks of the prior art, could be prepared by combining a water miscible solvent, such as alcohol, a salt in solid form and water.
It is essential to the present invention that the salt is present from about 30% to about 70% by weight of the composition at 20xc2x0 C. in the form of a solid phase comprising crystals of the salt. The composition will therefore comprise a salt in saturated aqueous solution of the salt, together with the crystal form.
The salt must have high solubility in water, and a low solubility in alcohol in order to provide the abrasion effect and be easily rinseable with water.
Due to the high solubility of salt in water (and poor solubility in alcohol), as the proportion of alcohol is increased, the lower the amount of salt needed to ensure presence of crystalline salt in the final composition. As the proportion of water is increased (and the proportion of alcohol is correspondingly decreased), the proportion of salt must also be increased in order to ensure the presence of inorganic salt in crystalline form in the final composition.
The inventor found to be an advantageous property of the composition of the present invention that the salt, which serves as a mechanical abrasive, does not clog the interior surfaces of the substrate; this being due to the water solubility of the salt resulting in the complete removal of any residual salt during the final step of rinsing the substrate after cleaning. Any other solid abrasives, in comparison, would stick to the organic deposits in the interior surfaces of the substrate and clog even zigzagged internal passages.
The solid salt must be of such hardness that it does not damage the surface of the substrate, but will nevertheless remove the organic deposit layers. Preferably the hardness is not greater than 5 on Moh""s.
The inventor also found out that a superior cleaning could be achieved in a very short period of time (about 20 seconds), without scrubbing, due to the interaction of the combination of the alcohol and the presence of the salt in crystal form. When the article to be cleaned is shaken, the crystal of the salt imparts a mechanical cleaning effect and supplements the chemical effects of the alcohol, and at the same time, the alcohol disinfects the surface being treated.
This represents a significant improvement over the prior art cleansing solutions, which required a minimum of one-half hour to soak, required scrubbing, and which are often not designed to disinfect. Further, in accordance with the present invention, it is only necessary to expose the internal surfaces (hard to reach surfaces) of the substrate to the cleansing composition and shake the article to be cleaned. This represents a significant savings over cleansing compositions that instruct the user to immerse the entire substrate in the cleansing solution.
The prior art cleansing solutions are thus not only comparatively ineffective in cleaning and sanitization ability, but they are annoying to use, and further require large quantities in order to immerse the device being cleaned, and thus are associated with significant cost.
The cleaning composition of the present invention in its basic form comprises:
a) a water miscible solvent;
b) an inorganic salt; and
c) water;
wherein from about 30 to about 70% weight of the total composition is comprised of the inorganic salt in crystalline form.
The liquid portion of the composition comprises from about 30 to about 70% of the total composition and the crystal form comprises from about 30% to 70% of the total composition.
The water miscible solvent: water ratio in the final composition is preferably in the range of from 9:1 to 2:1, preferably 8:1 to 5:1.
In a second preferred embodiment the cleaning composition for removing organic deposit comprises:
a) a water miscible solvent;
b) an inorganic salt;
c) water;
d) a terpene;
e) an anti-bacterial agent; and
f) at least one surfactant selected from the group consisting of anionic surfactant, non-ionic surfactant, amphoteric surfactant and mixtures thereof;
wherein from about 30 to about 70% weight of the total composition is comprised of the inorganic salt in crystalline form.
The present inventor also discovered that the defects of prior art liquid cleaning composition can be minimized or overcome through the incorporation therein of a specified level of a terpene material in combination with a polar solvent of specified water-solubility characteristics.
Although the terpenes, as a class, have limited water-solubility, it has now been found that they can be incorporated into liquid cleaning compositions in homogeneous form with the ability to provide excellent cleaning characteristics across the range of water hardness or grease/oily soils and inorganic particulate soils, as well as on shoe polish, marker ink, bath tub soil, etc, and excellent shine performance with low soil re-deposition and little or no propensity to cause filming, streaking, or spotting on surfaces washed therewith.
A notable feature of the instant composition is the suds-suppression effectiveness of the terpenes in liquid compositions based on surfactants. Thus, it is notoriously difficult to control the sudsing behavior of the surfactants in a cost-effective manner using conventional suppression agents such as soaps, waxes, etc. The terpenes are thus particularly valuable in this respect.
The second embodiment further includes an antibacterial agent. The introduction of an antibacterial into the equation results in additional problems for cleaning efficacy. For example, triclosan has very poor solubility in alcohol and generally requires the presence of surfactant to solubilize it, but certain surfactants have deactivating effects on the degerming properties of the antibacterial agent.
Accordingly, the surfactant system in the formulation of the present invention comprises a synergistic mixture of two or more surfactants. A first surfactant is selected for high solubilization of hydrophobic antibacterial agent, e.g., triclosan and the terpene. A second surfactant acts to aid in the solubilization of the first surfactant in the solvent, such that the total amount of surfactants is minimized. This two-stage solubilizing effect is important as it aids in the long-term shelf stability of the formulation.
The concentration of surfactant in the overall composition is dependent on a number of factors including the concentration of the alcohol, the concentration of the terpene, and the concentration of the antibacterial agent.
The addition of water miscible solvent to the composition assists in improving the dispersability and/or miscibility of the terpene and antibacterial agent in the composition.
It has also been surprisingly found that the composition of the present invention has a very high disinfecting property; this believed to be attributable to the high concentration of water miscible solvent and terpene.
In a third preferred embodiment, the present invention felt the necessity to provide a cleaning composition that was just as fast and effective as his previous compositions, but with less alcohol and more natural ingredients in other to satisfy customers with allergy problems or customers that prefer natural products.
In this embodiment, the water miscible solvent was limited to an alcohol derived from natural resources, such as SD 40 alcohol, and a terpene from a natural source, such as D-limonene.
It is essential that all the compositions of the present invention provide a sufficient amount of a salt in crystalline form, as an abrasive agent, which provides improved cleaning characteristics, specially in the hard to reach surfaces, with little tendency to cause filming or streaking on washed surfaces. Importantly, the abrasives used herein are non-detrimental to surfaces cleansed with the present compositions.
The cleaning composition has a number of other advantages relative to existing cleaners. In some applications, the cleaning composition provides an all-purpose cleaner that can replace existing caustic and non-caustic cleaners. The cleaning composition thereby reduces the labor and time required to clean the substrate. The cleaning composition is environmentally benign.
There has thus been outlined, rather broadly, the more important features of the invention in order that the detailed description thereof that follows may be better understood, and in order that the present contribution to the art may be better appreciated. There are, of course, additional features of the invention that will be described hereinafter and which will form the subject matter of the claims appended hereto.